core

## Degrees of Freedom for Features in QuickAlign

The Auto-align algorithms are based on GD&T datum precedence principles and the native degrees of freedom (DOF) of each feature type.

DOF of Supported Features

The supported features are grouped into the following six DOF-based cases, detailed in this table:

DOF Case | Feature Types | DOF Constraints
Planar | Planes, 3D Widths | R1 R2 T3
Axial | Cylinder, 3D lines, Cones* | R1 R2 T1 T2
2D Line | Lines (on a surface), 2D Widths | R1 T2
1D Point | Vector Points, Round Slots*, Square Slots* | T1
2D Points | Circles, Ellipses*, Edge Points, Angle Points | T1 T2
3D Points | Spheres, Corner Points | T1, T2, T3

* These features are treated differently in the QuickAlign algorithm:

- Cone features are treated as cylinders.

- Ellipses are treated as circles.

- Slot features (both round and square) are treated as one-dimensional vector points with their surface normal vector pointing in the direction of the slot width.

Table Key:

R1 - Rotation DOF about the first coordinate axis

R2 - Rotation DOF about the second coordinate axis

T1 - Translation DOF in first coordinate axis direction

T2 - Translation DOF in the second coordinate axis direction

T3 - Translation DOF in the third coordinate axis direction